Waste ink disposal means for spray printing devices

ABSTRACT

An inexpensive and efficient device which guarantees a satisfactory draining of waste ink accumulating on a rejection shutter in a spray printing device comprises a discharge channel member positioned below the rejection shutter and inclined from the horizontal by approximately 3*. The discharge channel member is formed of an elongated strip of sheet material bent at several points parallel to its length and joined to the rejection shutter to form a groove along their intersecting portions which groove will exert a capillary influence on the waste ink and thereby cause it to drain to a waste ink receptacle.

[11] 3,826,192 [451 July 30, 1974 1 wAsTE INK DISPOSAL ME NS FOR SPRAY PRINTING DEVICES [75] Inventors: Erich Kattner; Klaus Bork, both of Munich, Germany [73] 'Assignee: Siemens Aktiengesellschaft, Berlin and Munich, Germany 22 Filed: Apr. 17, 1972 21 Appl. No.: 244,492

[30] Foreign Application Priority Data Apr. 21, 1971 Germany 2119427 [52] US. Cl 101/335, 101/327, 101/426, 2 W 346/75, 61/15 [51] Int. Cl. B411 31/00, 601d 15/18 [58] Field of Seareh.... 346/75; 61/14, 15; 47/52; 101/327, 366, 335, 426

[56] References Cited UNITED STATES PATENTS 2,392,521 1/1946 Chollar 101/327 2,663,257 12/1953 Dudis 101/327 2,897,753 8/1959 Erzingcr 101/148 3,060,429 10/1962 Winston 197/1 R 3,373,437 3/1968 Sweet et a1. 346/75 3,570,275 3/1971 Weber et a1. 101/366 X 3,611,422 10/1971 Rourke 346/75 3,641,583 2/1972 MetZ 346/75 Primary ExaminerRobert E. Pulfrey Assistant Examiner-E. H. Eickholt Attorney, Agent, or Firm-Hill, Gross, Simpson, Van

Santen, Steadman, Chiara & Simpson 57 ABSTRACT An inexpensive and efficient device which guarantees a satisfactory draining of waste ink accumulating on a rejection shutter in a spray printing device comprises a discharge channel member positioned below the rejection shutter and inclined from the horizontal by approximately 3. The discharge channel member is formed of an elongated strip of sheet material bent at several points parallel to its length and joined to the rejection shutter to form a groove along their intersecting portions which groove will exert a capillary influence on the waste ink and thereby cause it to drain to a waste ink receptacle.

4 Claims, 3 Drawing Figures BACKGROUND OF THE INVENTION I In addition to the generally known contact printing procedure it is known to apply predetermined indicia to a recording carrier by means of a jet spray of dyed liquid. In these devices an electromagnetic field corresponding to the shape of the indicia which is to be recorded causes the spray of ink to be deflected to assume theconfiguration of the magnetic field. Whereas the means of creating the liquid jet and causing it to assume' predetermined configurations upon a recording material is known in the art there has not been an adequate solution in the prior art to the problem of undesirable drop formation occurring both at the time the jet spray is formed at the beginning of the recording process and at the time the jet spray is subsequently interrupted with the ending of the recording process.

In order that these undesired drops do not fall onto the material on which the matteris to be recorded, a rejection shutter is normally provided for the reception of these drops in an area below the area where the ink would normally be received. Since this undesirable drop formation usually involves drops of larger than normal size these larger drops of ink at the beginning and end of the recording process are directed by the spray printing means onto the rejection shutter. That is, the actual recording and printing process will only be allowed to take place if the liquid jet is optimally formed.

A common practice where short, spaced indicia are to be printed, as for example when recording individual letters within a line, is to not interrupt the liquid jet spray at all but to deflect it onto the rejection shutter during those times during which the printing is not to take place. In this situation it is advantageous to arrange a rejection shutter for the waste ink directly below the point on the recording material where the image is to be recorded. In the usual case where the images are to be recorded along a line the ink jet spray head moves along this line in generally the same position relative to the upper edge of the rejection shutter.

We have found it is desirable to somehow convey the waste or excess ink which hits the rejection shutter to a common waste receptacle. One such means which we tried was a gutter positioned below the rejection shutter. Since, however the amount of excess ink is caught by the rejection shutter is not very large we found that the waste ink which collected in the channel did not flow into the waste container but thickened and dried because of the evaporation of the liquid carrier of the ink. This accumulation is unsightly and requires regular attention and maintenance.

SUMMARY OF THE INVENTION According to our invention the problems of the prior art are overcome by an inexpensive and efficient means which guarantees a satisfactory draining of the waste ink which accumulates on the rejection shutter to a waste ink reciprocal. We have solved the prior art problems by providing a discharge channel in the form of a groove having parallel sides which exerts a capillary influence on the waste ink. The groove is inclined from the horizontal and has a waste ink receptacle at its lower end into which the ink will be drawn.

According to a preferred embodiment of our invention the groove extends along the line where the images are to be printed and at a slight angle of inclination of approximately three degrees towards the waste container. The groove is formed in a generally V-shaped configuration so that the surface of a liquid where it is in contact with the groove is elevated or depressed depending upon the relative attraction of the molecules of the liquid for each other and for that of the material of the groove so that a capillary action results to move the waste ink along the groove to the waste ink receptacle. At the end of the discharge channel groove the collected waste ink will accumulate in drops and pass into the waste receptacle.

In another embodiment of our invention the dis charge channel which extends below the line where the images are to be recorded includes a groove having a capillary influence on the waste ink and in addition includes a vertical discharge channel arranged in the area of the waste ink container so that ink from the groove passing below the rejection shutter is conveyed by a capillary action directly to the waste ink container. The vertically extending groove may be spaced a small distance from the lower end of the groove which runs below therejection shutter since the vertical discharge channel groove will attract the ink by means of capillary action and direct it to the waste container.

In order to reduce the production cost of our waste and collection device to a minimum we have found that forming-the discharge channel of an elongated sheet metal strip bent so that the lower area along its length is bent away from the upper area along its length and connecting this discharge channel below the rejection shuttereffects great economies. In practice we have found that where the rejection shutter is formed of sheet metal the discharge channel may be spot welded thereto along its length.

The rejection shutter may take the form of a recessed portion on a piece of flat metal with its bottom edge inclined at the same angle as the discharge channel. The discharge channel is attached along this point of deformation to form a V-shaped groove which has a very high capillary action to attract excess waste ink which may be accumulated on the rejection shutter.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts embodied in the disclosure, and in which:

FIG. 1 is a perspective schematic illustration of a spray ink printing device having a first discharge channel slightly inclined from the horizontal and a second discharge channel generally vertically inclined whereby ink accumulating on a rejection shutter is transported by capillary action to a waste receptacle;

FIG. 2 is an schematic enlarged cross sectional representation taken along the lines Il-II in FIG. 1 with a ink jet spray nozzle schematically depicted directing a spray against the rejection shutter; and

FIG. 3 is a schematic enlarged fragmentary top plan view taken substantially along the line III-Ill of FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. I there may be seen the upper portion of a generally cylindrical platen means 1 which supports a sheet-like recording carrier means 2. A liquid jet spray ink recording head 3 which sprays out ink against the recording carrier 2 as schematically illustrated by the line 4 is movable along a line across the width of the recording carrier 2 whereby images may be recorded on the carrier 2 by the influence of an electromagnetic field on the atomized particles of liquid ink in accordance with means known in the prior art which therefore need not be set forth in further detail here. During the spray jet printing process the spray is directed as schematically shown by the line 4 toward the recording carrier 2. However when there are gaps between the indicia to be formed on the recording carrier 2 the liquid spray jet recording head 3 is directed as indicated schematically by the line 4a against a rejection shutter 5 which is arranged below the area 4b where the images are to be formed on the carrier material 2.

The deflection of the jet spray line 4 to direct the spray against the rejection shutter 5 avoids the necessity of stopping and restarting the jet spray which stopping and starting causes undesirable spray jet drop formation and theaccompanying undesirable ink spots on the recording carrier.

As shown the rejection shutter 5 may be formed as a recess in a flat metal support plate which recess includes a vertical corrugated surface 50 outwardly sloping side wall portions 5b and 5d and a downwardly sloping bottom wall portion 50. The wall portion 50 is inclined from the horizontal along the length of the rejection shutter 5. A discharge channel 6 is arranged below the recording area 4b and below the rejection shutter portion 5a in general alignment with the wall portion 50. We have found that inclining the discharge channel 6 and the wall portion 5c at an angle of approximately 2 /2 to 3 with respect to the horizontal provides excellent results.

As shown in FIG. 2, the discharge channel 6 is formed by the lower portion 5c of the rejection shutter 5 and an elongated sheet metal strip 7 having an upper portion 7a bent away from the plane of a lower portion 7b. In practice we have found that where the strip 7 is sheet metal and where the support plate 20 is metal they may be connected to each other by spot welding along the lower portion 7b of the strip 7. The bend lines between the portions 5c, 20 and 7a, 7b have bend radii so that when the strip 7 is attached to a member 20 in tight face-to-face relation as shown in FIG. 2 what may be characterized as a V-shaped groove 8 is formed between the members adjacent the radii. Because of its configuration this groove exerts a very distinct capillary action on waste ink which accumulates on the rejection shutter and flows downwardly as shown by the dotted line 5e. As a result, even if only a very small amount of ink is received by the rejection shutter it will be drawn to the groove 8 and will be caused to flow along the groove 8 by capillary action and under the influence of a slight downward inclination of the discharge channel.

The waste ink thus flows down the groove 8 to a lower end 8a in the area of a waste ink receptacle 9 which is arranged thereunder.

In order to improve the flow of the waste ink to the waste ink receptacle 9 from the end 8a of the groove 8', a vertically inclined discharge channel means member 11 (FIGS. 1 and .3) is arranged in the area of the waste receptacle 9 to direct the flow directly to the waste receptacle. The channel member 11 is constructed of a sheet metal strip having a first portion 1 1a bent out of the plane of a second portion 11b. The strip 11 is attached to the support plate 20 by spot welding or other suitable means as set forth with respect to the strip 7 and works under the principles of capillary action providing a vertical discharge channel to the waste ink receptacle 9. Because of the very effective capillary action of the channel groove 10 the channel member 11 may be spaced from the end 8a of the groove 8 and still attract the ink flowing from the groove 8.

The waste ink receptacle 9 which accepts the ink from the groove 10 may be filled with cotton puffs which completely absorb the relatively small amount of waste ink. If the cotton puffs become completely saturated they may be disposed of together with the waste container 9 which may be very inexpensively manufactured. By means of the invention herein we have provided a very effective and yet extremely economical solution to the problem of waste ink disposal in a jet ink printing apparatus.

Many changes and modifications may be made in the invention by one skilled in the art without departing from the spirit and scope of the invention, and it is to be understood that we intend to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of our contribution to the art.

We claim:

1. Waste ink disposal apparatus for excess ink in a spray printing device comprising:

rejection shutter means below a recording area,

adapted to receive a spray of ink;

upwardly opening discharge channel means positioned below the upper edge of said rejection shutter means whereby ink hitting said shutter means will drain into said channel means;

said channel means providing a capillary groove extending therealong inclined slightly downwardly and along which the waste ink flows toward waste ink receiving means at its lower end receptive of the ink which drains into the channel means;

said groove providing for capillary action between it and the waste ink to accelerate conveying the waste ink to the receiving means whereby to avoid thickening and drying of the ink in the channel means; and

a vertical capillary channel adjacent to said lower end of said groove, said vertical channel providing for capillary influence on said waste ink to accelerate conveying said waste ink to said waste ink receiving means.

2. Waste ink disposal apparatus for excess ink in a spray printingde'vice comprising:

rejection shutter means adapted to receive a spray of ink-below a recording area;

upwardly opening discharge channel means, positioned belowv the upper edge of said rejection shutter means whereby ink hitting said shutter means will drain into said channel means;

said channel means providing a capillary groove extending therealong inclined slightly downwardly and along which the waste ink flows toward waste ink receiving means at its lower end receptive of the ink which drains into the channel means;

said groove providing for capillary action between it and the waste ink receiving means whereby to avoid thickeningand drying of the ink in the channel means;

said discharge channel means comprising an elongated member having an upper portion bent out of the plane of a lower portion' along a bend line, said lower portion being tightly'connected with the rejection shutter means to form said capillary groove in V-shape at the intersection of the rejection shutter and the bend line; and

said rejection shutter means comprising a member having a planar portion recessed therein directly below said recording area, said planar portion joined to the remainder of said member by opposite side surfaces and a bottom surface, said bottom surface providing a downwardly sloping wall paral-' leling said bend line and said intersection being at the lower edge of said sloping wall.

3. Apparatus according to claim 1, including a vertical capillary channel adjacent to said lower end of said groove, said vertical channel providing for capillary influence on said waste ink to accelerate conveying said waste ink to said waste ink receptacle.

4. A method of waste ink disposal for excess ink in a spray device in which the excess ink is received by rejection shutter means below a recording area and wherein the ink is liable to thicken and dry by evaporation, comprising:

receiving the excess ink from said rejection shutter means in upwardly opening discharge channel means positioned below the upper edge of the rejection shutter means;

effecting accelerated capillary conveyance of the ink by capillary action along a capillary groove in said channel means inclined downwardly toward a discharge end; and

receiving the wasteink from the lower end of said channel means capillary groove in a vertical capillary groove extending therebelow and thereby gravitationally and by capillary action accelerating movement of the waste ink to waste ink receiving means below said vertical capillary groove. 

1. Waste ink disposal apparatus for excess ink in a spray printing device comprising: rejection shutter means below a recording area, adapted to receive a spray of ink; upwardly opening discharge channel means positioned below the upper edge of said rejection shutter means whereby ink hitting said shutter means will drain into said channel means; said channel means providing a capillary groove extending therealong inclined slightly downwardly and along which the waste ink flows toward waste ink receiving means at its lower end receptive of the ink which drains into the channel means; said groove providing for capillary action between it and the waste ink to accelerate conveying the waste ink to the receiving means whereby to avoid thickening and drying of the ink in the channel means; and a vertical capillary channel adjacent to said lower end of said groove, said vertical channel providing for capillary influence on said waste ink to accelerate conveying said waste ink to said waste ink receiving means.
 2. Waste ink disposal apparatus for excess ink in a spray printing device comprising: rejection shutter means adapted to receive a spray of ink below a recording area; upwardly opening discharge channel means positioned below the upper edge of said rejection shutter means whereby ink hitting said shutter means will drain into said channel means; said channel means providing a capillary groove extending therealong inclined slightly downwardly and along which the waste ink flows toward waste ink receiving means at its lower end receptive of the ink which drains into the channel means; said groove providing for capillary action between it and the waste ink receiving means whereby to avoid thickening and drying of the ink in the channel means; said discharge channel means comprising an elongated member having an upper portion bent out of the plane of a lower portion along a bend line, said lower portion being tightly connected with the rejection shutter means to form said capillary groove in V-shape at the intersection of the rejection shutter and the bend line; and said rejection shutter means comprising a member having a planar portioN recessed therein directly below said recording area, said planar portion joined to the remainder of said member by opposite side surfaces and a bottom surface, said bottom surface providing a downwardly sloping wall paralleling said bend line and said intersection being at the lower edge of said sloping wall.
 3. Apparatus according to claim 1, including a vertical capillary channel adjacent to said lower end of said groove, said vertical channel providing for capillary influence on said waste ink to accelerate conveying said waste ink to said waste ink receptacle.
 4. A method of waste ink disposal for excess ink in a spray device in which the excess ink is received by rejection shutter means below a recording area and wherein the ink is liable to thicken and dry by evaporation, comprising: receiving the excess ink from said rejection shutter means in upwardly opening discharge channel means positioned below the upper edge of the rejection shutter means; effecting accelerated capillary conveyance of the ink by capillary action along a capillary groove in said channel means inclined downwardly toward a discharge end; and receiving the waste ink from the lower end of said channel means capillary groove in a vertical capillary groove extending therebelow and thereby gravitationally and by capillary action accelerating movement of the waste ink to waste ink receiving means below said vertical capillary groove. 